At funeral services for Nathan Krasnopoler at Sol Levinson and Bros. Funeral Home on Aug. 12, the 20-year-old was remembered by a Johns Hopkins University professor for his "keen and incisive intellect."

Mr. Krasnopoler died Aug. 10 at Gilchrist Center in Columbia of a severe, irreversible brain injury sustained Feb. 20 when he was hit by a motorist while riding his bicycle on West University Parkway near the Hopkins Homewood campus.

"Nathan was very bright, very creative and very self-motivated," said Edward R. Scheinerman, professor in the Johns Hopkins University's department of applied mathematics and statistics, who is also vice dean of education at the Whiting School of Engineering.

"As fascinating and far-ranging as Nathan's interests were, they don't begin to describe the depth of a young man … who skillfully articulated his cherished beliefs, and who had a circle of devoted and loving friends," Dr. Scheinerman said in his eulogy.

"He was also an avid reader — I remember when we were hiking at Yosemite, he'd pull out a book when we stopped to rest," said his mother, Susan Cohen, an attorney. "He even took a book to his senior prom in case he got bored."

Mr. Krasnopoler was a 2009 graduate of the Shoshana S. Cardin School.

By the time he had arrived at the Northwest Baltimore high school, he had already progressed beyond its math curriculum, said Ian Blumenfeld, his math teacher there for three years.

"He was supremely talented, and I was basically hired specifically to teach Nathan and another student. He had a feel for the beauty of math, and because of his abilities was way off the charts," said Mr. Blumenfeld, who now works in research.

"Nathan really stood out and had the potential to do whatever he wanted in the technical research field," he said. "He was very contemplative and a nonconformist, but in a quiet way. He had values and stuck to them."

"While he was very attached to his computer, he enjoyed the outdoors. He was a very well-rounded person, and his teachers always respected his intellect and out-of-box thinking," his mother said.

"He was more interested in the bicycle for transportation and had taken up running. He was a barefoot runner, a kind of a back-to-nature type of runner," his father said.

"He was not a risk taker and really disliked driving. He really didn't want anything to do with it," his mother said. "He either walked or rode his bike. He told me once that he didn't want to live in the suburbs and wanted to live in a city."

A computer science and math student who was in his junior year at Hopkins, he quickly absorbed complicated concepts and was a whiz at finding "creative solutions to intriguing and difficult computer problems," Dr. Scheinerman said in his eulogy.

"Nathan enjoyed tinkering with computers and software," he said to the mourners. "Just for fun, he created his own functional programming extension to the C computer language. If you're not a computer scientist, let me explain that what Nathan did was highly sophisticated and demonstrated a mature understanding of computer languages."

In a telephone interview, Dr. Scheinerman said that Mr. Krasnopoler was "gently quiet in his class, but would speak up and ask insightful questions."

Alex Rozenshteyn, a computer science major, had been Mr. Krasnopoler's friend since his freshman year and was his roommate.

"Nathan was never afraid to express an opinion, and whether it might be popular or not, he'd express it," he said.

"He was interested in locally grown organic sustainable food and wanted to learn how to cook it," his mother said, who added that her son as a youngster became an excellent baker of pies and desserts, and loved giving them away to friends as gifts.

"The morning of the accident, he had been to Waverly Market, and he had a backpack full of food," his father said.

When Mr. Krasnopoler's parents were told that his recovery was unlikely, they considered organ donation.

"We wanted some good to come out of this tragedy and thought we could donate one of Nathan's kidneys," his mother said. "He was a very healthy kid who neither drank or smoked."

"If he had been on a ventilator and not breathing on his own, it would have been a very easy thing to do," his father said.

"We thought it was something we could offer from this senseless tragedy," his mother said. "Both Maryland and Hopkins took us seriously and gave us good consideration."

In their son's memory, the family established the Nathan Krasnopoler Memorial Fund at Hopkins' Whiting School of Engineering.

In addition to his parents, who live in Ellicott City, Mr. Krasnopoler is survived by a brother, Elliot Krasnopoler of Ellicott City; a sister, Emma Krasnopoler of Ellicott City; his paternal grandfather, Irv Krasnopoler of Pittsburgh; and his maternal grandmother, Charlotte Cohen, also of Pittsburgh.

Dominic J. Pistorio, a Baltimore homebuilder and World War II veteran who lived to 104 and wore suits almost every day until the last week of his life, died of pneumonia at Howard County General Hospital on March 25.

A Mass of Christian burial for William "Bill" Toohey, the former Baltimore County Police Department spokesman who died Thursday at 69, will be held at 11 a.m. Tuesday at Our Lady of Hope Catholic Church, 1727 Lynch Road in Dundalk. The family will receive friends Sunday and Monday from 2 p.m....

Dr. Stanley Kogan, a retired Baltimore oral-maxillofacial surgeon who had been chief of the department of dentistry at Sinai Hospital and what is now Northwest Hospital in addition to maintaining a private practice, died March 20 at his Pikesville home of cardiopulmonary disease. He was 84.